Throttle kill switch

ABSTRACT

A rotating control lever and electrical switch for mobile vehicles wherein the pivot member for the lever is translationally movable to act as the electrical conducting switch. The pivot member is relatively loosely confined in the lever mounting bracket, and a pair of electrical conduits are secured to the bracket in spaced relation to make selective contact with the pivot member upon its translational movement. A spring engages the pivot to urge it translationally toward one of its switch positions, while selective rotation of the lever overrides the spring bias and moves the pivot translationally to another switch position.

[221' Filed:

United States Patent Carlson [54] THROTTLE KILL SWITCH [72] inventor:John A. Carlson, Wichita, Kans.

[73] Assignee: Conchemo, Incorporated, Kansas City, Mo.

Oct. 1, 1971 21 Appl. No.: 185,733

521 U.S.Cl. ..200/6l.87, 200/157 [51] Int. Cl. ..H0ll\ 9/06 [58] Fieldof Search..200/6l.85, 61.87, 61.88, 6l.89,

I ZOO/61.9, 61.91, 157

[56] References Cited UNITED STATESPATENTS 3,273,552 9/1966 Plath..200/6l.89X

1151 3,694,596 1451 Sept. 26, 1972 Primary Examiner-Robert K. SchaeferAssistant ExaminerM. Ginsburg Attorney-Schmidt, Johnson, l-lovey &Williams [5 7] ABSTRACT A rotating control lever and electrical switchfor mobile vehicles wherein the pivot member for the lever istranslationally movable to act as the electrical conducting switch. Thepivot member is relatively loosely confined in the lever mountingbracket, and a pair of electrical conduits are secured to the bracket inspaced relation to make selective contact with the pivot member upon itstranslational movement. A spring engages the pivot to urge ittranslationally toward one of its switch positions, while selectiverotation of the lever overrides the spring bias and moves the pivottranslationally to another switch position.

8 Claims, 6 Drawing Figures I PATENTED SEPZG I972 3 694 596 Jam 4. Car/50/? This invention relates to mechanical control levers havingautomatically operated electrical switching means associated therewith.

A highly important safety feature for mobile vehicles having extensivethrottle control linkage actuated by hand or foot pedals, is theinclusion of an automatic safety switch that stops the engine wheneverthe throttle linkage malfunctions. Such an automatic kill switch can beconsidered requisite for certain type vehicles, such as snowmobileshaving exposed hand control levers and linkage highly susceptible tofreezing, sticking or breaking. The accelerator or throttle linkagenormally includes a return spring urging the throttle to a closed oridling position; however, upon malfunction of the control linkage thereturn spring bias will be relieved and the throttle will remain in afully open position.

To obviate this dangerous condition, therefore, it becomes highlydesirable to provide an electrical switching arrangement that actsautomatically, whenever the throttle malfunctions, to complete a circuitto ground or otherwise disable the engine ignition circuit and bring thevehicle to an emergency stop. Switches of the class described may alsobe used in other applications, such as automatically opening and closingbrake light circuitry in response to actuation of the brake pedal.

' Throughout the specification, the ignition circuitry is referred to asbeing open to denote the grounding or otherwise disabling condition ofthe ignition circuitry; and conversely, the ignition circuitry isdescribed as being closed to denote the opposite, enabling or completedcondition during which normal ignition and vehicle operation occurs.

A broad object of the invention is to provide an automatic safety switchof the character described which forms part of the control leverassembly.

It is an important object of the invention to provide automaticelectrical switch means of the class described which operates both inresponse to actuation of mechanical control means and in response tomalfunction of the latter means.

A more particular object of the invention is to pro- 2 positioning thelever near said position, urging the electrical conducting pivot memberto a circuit closing position permitting operation of the vehicleengine.

Another object of the invention is to provide an electrical circuitswitch in combination with a vehicle brake lever which automaticallyturns on the brake lights upon actuation of the brake lever.

Still a further object of the invention is to provide an electricalswitch assembly of the class described which is simple and highlyreliable in design.

Briefly, one form of the invention comprises a throttle control leverpivotally mounted upon a bracket base secured to the vehicle, with acontrol cable fastened to the lever and normally being under tension tobias the lever to an engine idling position. The lever pivots on acylindrical bar loosely confined within an opening in the lever mountingbracket so as to be translationally movable in a plane containing thelever pivot axis. A pair of electrical conductors are secured upon thebracket and extend into the bracket opening so as to make and breakcontact with the electrical conducting pivot bar upon its translationalmovement. A spring member in the bracket urges the pivot bartranslationally to a position contacting the electrical conductors so asto open the vehicle ignition circuit and prevent its operation. Uponselective rotation of the vide a vehicle electrical ignition switchwhich operates automatically in response to malfunction of the vehiclecontrol linkage.

A further object of the invention is to provide a rotatable acceleratorcontrol leverspring biased to an idling position, and an electricalswitch automatically disabling or opening the engine ignition circuitupon failure of the spring to return the lever to the idling position.

A more particular object in accordance with the preceding object is toprovide a control lever pivot member which is loosely contained withinthe lever mounting bracket soas to be translationally displaceablebetween positions opening and closing the ignition circuit, and springmeans for normally urging said electrical conducting pivot member to aposition closing the ignition circuit to permit operation of the vehicleengine.

. Yet another object in accordance with the preceding object is toprovide a tension spring control cable normallybiasing the lever to itsidling position and, upon lever away from its idling position the leverurges the pivot bar translationally away from the conductors so as toclose the ignition circuit and permit operation of the vehicle. Thelever is arranged on the mounting bracket so that as it nears the idlingposition, the control cable tension acts against the spring and movesthe pivot bar to the circuit closing position. Upon loss of the cabletension bias through malfunction, the biasing spring moves the pivot barto a circuit opening position to stop the engine.

Other objects and advantages of the present invention are specificallyset forth in or will become apparent from the following detaileddescription of preferred embodiments of the invention and theaccompanying drawings, in which:

FIG. 1 is a fragmentary perspective view of a portion of a mobilevehicle utilizing the present invention;

FIG. 2 is a front elevational view of one form of control lever andelectrical switch assembly as contemplated by the present invention;

FIG. 3 is a side elevational view of the control lever and electricalswitch assembly;

FIG. 4 is a rear elevational view of the control lever and electricalswitch assembly;

FIG. 5 is a longitudinal cross section viewed along lines 5-5 of FIG. 4;and

FIG. 6 is a transverse cross section as viewed along lines 6-6 of FIG. 6of the electrical switch portion of the lever bracket.

FIG. 1 illustrates the forward end of a snowmobile 10 or the like havingbrake and throttle control levers 12 and 14 secured upon the steeringhandle bars 16. Referring to FIGS. 2-4, which illustrate the throttlecontrol lever 14 in greater detail, the throttle control generallyincludes a mounting bracket 18 having a central opening 19 accepting thehandle bar, and a lever 20 pivotally mounted upon bracket 18. Themounting bracket and lever are preferably molded of high impact,insulative plastic material. A boss 22 at the rear of holes 32 alignedon opposite ends of the lever. As best seen in FIG. 6, a metal bar pivot34 extends through the lever pivot openings 32 and an intermediateenlarged opening 36 in the bracket 18 enclosed on three sides by thelever. In the preferred form, pivot bar 34 is formed from a cylindricalstock of electrical conducting metal having good bearingcharacteristics, andis secured to lever 20 by conventional snap rings38. Lever 20 is pivotal relative'pivot bar 34 so as to rotate relativeto the mounting bracket and displacethe control cable 26 to selectivelyvary engine throttle and vehicle speed.

Referring to FIG. the control cable includes a control wire 40 engagingthe lever at 42, and a spirally wound protective sheath 44 surroundingthe wire. Through conventional linkage the control cable connects withthe engine throttle control whereby upon counterclockwise rotation oflever 20, wire 40 is pulled leftwardly to increase engine speed. Athrottle spring (not shown) is coupled with cable 26 to pull samerightwardly under a tension depicted by arrow 41, and thereby-urge leverto rotate clockwise about pivot bar 34 to an engine idle position whereguide portion 30 of the mounting bracket stops the lever from fartherclockwise rotation. Upon actuating the lever by applying operatingforces to lever surface 46, the lever 20 rotatescounterclockwise inopposition to the bias of this cable tension4l to pull the control wire40 leftwardly.

An electrical plug-in bracket 48 is mounted upon the lower front face oflever bracket 18 so as to accept spaced electrical current conductingmetal strips 50 and 52 positioned to extend from the mounting bracketopening 36 so as to form terminals for connection into the engineignition circuitry (not shown). In the preferred form, each electricalconductor has an enlarged opening accepting and surrounding the pivotbar 34, and has rearwardly positioned surfaces 54 in contactablerelationship to pivot bar 34. A compression spring 56 is compressedbetween the electrical plug-in 48 and pivot bar 34 so as to bias thepivot bar toward contact with electrical conducting surfaces 54.

As shown in FIGS. 5 and 6, the bracket opening 36 loosely confines pivotbar 34 to permit translational movement of the bar from a positionengaging front wall 58 as shown in FIG. 6, to a position contacting theconductor surfaces 54. Through this arrangement the pivot bar 34 isurged rightwardly against surface 58 whenever operating forces areapplied to lever 20 to rotate same counterclockwise away from the idlingposition. In the absence of such operating forces, spring 56 urges pivotbar 34 the opposite direction into contact with the electricalconductors. Conductors 50 and 52 are. arranged in the ignition circuitryin such a manner whereby closing the circuit between the two conductorscompletes a circuit to ground to open or disable the ignition to preventengine operation, i.e., whenever the pivot bar is contacting surfaces54, and permits normal engine operation when the circuits between theconductors are not closed, as whenever the pivot bar is in a position asshown in FIG. 6.

It will be apparent to those skilled in the art that the conductors maybe differently connected within the ignition circuitry so that thecircuit between conductors 50, 52 must be closed, rather than opened, topermit engine operation. It will also be apparent that for sucharrangement the conductor contact surfaces 54 can be reversed and placedon the right side, rather than left side, of pivot bar 34 as viewed inFIG. 6. This one change will duplicate the operation described above,with the operating forces moving pivot bar 34 rightwardly again to anignition-enabling position- (making contact with the conductors) inopposition to nition-disabling position (breaking contact with theconductors).

Returning to the illustrated embodiment of the invention, a stop member60 is incorporated on the lower portion of the lever mounting bracket 18so as to provide a cam surface engaging a dog extension 62 of lever 20.The stop 60 is also engageable with lever surface 66 to limitcounterclockwise lever rotation. The engagement of dog 62 and stop 60permits normal operation of the engine in the idling position. Stop 60engages the dog 62 below pivot bar 34 as viewed in FIG. 3, on theopposite side at which control cable wire 40 is secured to the lever,and is positioned to contact the lever as the latter rotates clockwiseto near its idling position. Thus, upon release of lever 20,-the biastension 41 pulls the lever clockwise in rotation about pivot 34 towardthe idling position until dog 62 engages stop 60. The bias of thecontrol cable then continues pulling the lever clockwise, but ratherabout the point of contact 64 between the lever and stop member 60. Thecontrol cable accordingly forces pivot member 34 to move rightwardly andout of contact with conductor surfaces 54. The bias presented by thecontrol cable tension normally holds the lever unattended in the idlingposition and holds the pivot bar in its FIG. 6 position to permit normalengine operation during idling.

Accordingly, during normal operation of the invention, the operatingforces applied upon lever 20 will overridethe bias of pivot spring 56and urge the pivot bar to the FIG. 6 position to close the ignitioncircuit and permit normal engine operation. Upon release of the handle,the cable control automatically returns to an idling position and itstension holds the pivot member out of contact with conductors 50 and 52to again permit normal operation.

Upon malfunction of the tension control cable, its bias upon the leverwill be relieved, and pivot spring 56 will push pivot bar 34 and thelever back leftwardly, to the position depicted in dashed lines in FIG.3, into engagement with the conductors to stop the engine. The vehicle,therefore, automatically comes to an emergency stop whenever the tensioncontrol linkage malfunctions.

In the embodiment illustrated, the combined efforts of the operatingforces and cable tension 41 normally hold pin 34 in itsignition-enabling position. Additionally, if desired, a detent mechanismmay be incorporated to assist in holding the pin in this position. Suchan arrangement, for instance a modified configuration of the throttle.The holding force exerted by such a detent would be less than the forceof spring 56 so that the latter could still move the pin to kill theengine whenever the tension cable malfunctions.

The present arrangement of rotatable control lever and automaticelectrical switch has fewer parts and is generally simpler in design,creating a switch highly reliable in operation, and durable in nature.This is accomplished primarily through utilizing a cylindrical pivot bar34 which also acts as the electrical switch member; The generally looseconfinement of pivot pin 34 within the mounting bracket reduces wear andincreases part life. In a preferred form of the invention the combinedelectrical switch and pivot, conductors 50 and 52, and spring 56 are allencased within the mounting bracket 18 for protection.

The brake control lever 12, generally identical in design to throttlelever 14 and therefore not shown in detail, comprises another embodimentof the invention. In particular, brake control 12 is the same asthrottle 14 except it has no engaging stop and dog members 60 and 62. Bythis arrangement the pivot biasing spring 56 continually urges the pivotbar leftwardly to a position opening the brake light circuitry (notshown) in the absence of application of operating forces on the brakelever. Upon actuating the brake control lever, the pivot pin 34 movesrightwardly to a position closingv the brake light electrical circuitryso as to turn on warning lights whenever the brakes are applied.

The foregoing detailed description of preferred forms of the inventionare to be considered exemplary in nature and not as limiting to thescope and spirit of the invention as set forth in the appended claims.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. In a control device having a rotatable actuating lever, controllinkage secured to said lever so as to be displaced upon rotation of thelever away from a first position, and first biasing means operativelyengaging said control linkage to urge the lever to rotate toward saidfirst position, wherein the improvement comprises:

an electrical conductor bar pivot member engaging said lever so as toprovide a pivot therefor;

a nonrotatable, insulative housing having an opening accepting saidpivot bar member whereby said lever rotates relative to said housing,said opening being sufficiently large to permit limited translationaldisplacement of said pivot bar member substantially in a planecontaining the pivotal axis of said lever;

a pair of electrical current conducting members affixed to said housingin contacting relation to said conductor bar pivot member, said barpivot member being translationally movable between one positioncontacting said current conducting members to close a circuittherebetween and another position opening the circuit between saidcurrent conducting members; and

second biasing means mounted in said housing and operatively engagingsaid conductor pivot bar member to urge the latter translationallytoward one of said circuit opening and closing positions, said leverbeing operable upon rotation away from said first lever position to urgesaid pivot bar member translationally to the other of said circuitopening and closing positions in opposition to the urgings of saidsecond biasing means.

2. The control device of claim 1, wherein said second biasing means urgesaid pivot member translationally toward said circuit closing position.

3. The control device of claim 1, wherein said second biasing means urgesaid pivot member translationally toward said circuit opening position.

4. The control device of claim 1, further comprising a stop memberattached to said housing engaging said lever as the latter nears saidfirst lever position and upon engagement providing a secondary pivotpoint for rotation of said lever, the control linkage and secondarypivot point being located on opposite sides of said translationaldisplacement plane whereby, upon engagement of said lever and stopmember, said lever is urged by said first biasing means to rotate aboutsaid secondary pivot point toward said first lever position and therebyforce said pivot bar member translationally to said other of saidcircuit opening and closing positions in opposition to said secondbiasing means.

5. The control device of claim 4', wherein said second biasing meansurge said pivot member translationally toward said circuit closingposition, and wherein said lever is urged by said first biasing means toforce said pivot bar member translationally to said circuit openingposition upon engagement. of said lever and stop member.

6. The control device of claim 5, wherein said second biasing means is acompressible spring extending translationally between said housing andsaid pivot bar member.

7. An automatic safety switch for vehicle controls having an acceleratorlever rotatably mounted upon a base, and an accelerator control cablesecured to the lever in such a manner as to normally bias the lever torotate toward an idling position and to be displaced in response toselective rotation of the lever away from said idling position, saidswitch comprising:

an electrical conductor pivot bar engaging said lever and carried withinan opening in said base to'provide a pivot for rotation of the leverrelative to the base, said base opening being sufficiently large topermit limited translational movement of said pivot bar substantiallyalong a plane containing the lever pivot axis;

a pair of electrical conducting members secured to said base andextending into said opening at spaced locations, said pivot bartranslationally movable between a position making contact with saidconducting members and a position breaking contact with said conductingmembers;

a spring mounted in said base opening operatively engaging said pivotbar to urge same translationally toward one of said pivot bar positions,said lever urging said pivot bar translationally to the other of saidpivot bar positions in opposition to said spring upon rotation of thelever away from said idling position; and

a stop member formed on said base on a side of said translationaldisplacement plane opposite the side at which said cable is secured tothe lever, said stop member engaging a first surface of said lever asthe lever nears said idling position whereby the bias of said controlcable thereupon urges said lever to rotate about the point of engagementof the lever and stop member toward said idling position, andsimultaneously urges said pivot bar translationally to said other ofsaid pivot bar positions in opposition to said spring so as to normallymaintain said pivot bar at said other position when the

1. In a control device having a rotatable actuating lever, control linkage secured to said lever so as to be displaced upon rotation of the lever away from a first position, and first biasing means operatively engaging said control linkage to urge the lever to rotate toward said first position, wherein the improvement comprises: an electrical conductor bar pivot member engaging said lever so as to provide a pivot therefor; a nonrotatable, insulative housing having an opening accepting said pivot bar member whereby said lever rotates relative to said housing, said opening being sufficiently large to permit limited translational displacement of said pivot bar member substantially in a plane containing the pivotal axis of said lever; a pair of electrical current conducting members affixed to said housing in contacting relation to said conductor bar pivot member, said bar pivot member being translationally movable between one position contacting said current conducting members to close a circuit therebetween and another position opening the circuit between said current conducting members; and second biasing means mounted in said housing and operatively engaging said conductor pivot bar member to urge the latter translationally toward one of said circuit opening and closing positions, said lever being operable upon rotation away from said first lever position to urge said pivot bar member translationally to the other of said circuit opening and closing positions in opposition to the urgings of said second biasing means.
 2. The control device of claim 1, wherein said second biasing means urge said pivot member translationally toward said circuit closing position.
 3. The control device of claim 1, wherein said second biasing means urge said pivot member translationally toward said circuit opening position.
 4. The control device of claim 1, further comprising a stop member attached to said housing engaging said lever as the latter nears said first lever position and upon engagement providing a secondary pivot point for rotation of said lever, the control linkage and secondary pivot point being located on opposite sides of said translational displacement plane whereby, upon engagement of said lever and stop member, said lever is urged by said first biasing means to rotate about said secondary pivot point toward said first lever position and thereby force said pivot bar member translationally to said other of said circuit opening and closing positions in opposition to said second biasing means.
 5. The control device of claim 4, wherein said second biasing means urge said pivot member translationally toward said circuit closing position, and wherein said lever is urged by said first biasing means to force said pivot bar member translationally to said circuit opening position upon engagement of said lever and stop member.
 6. The control device of claim 5, wherein said second biasing means is a compressible spring extending translationally between said housing and said pivot bar member.
 7. An automatic safety switch for vehicle controls having an accelerator lever rotatably mounted upon a base, and an accelerator control cable secured to the lever in such a manner as to normally bias the lever to rotate toward an idling position and to be displaced in response to selective rotation of the lever away from said idling position, said switch comprising: an electrical conductor pivot bar engaging said lever and carried within an opening in said base to provide a pivot for rotation of the lever relative to the base, said base opening being sufficiently large to permit limiTed translational movement of said pivot bar substantially along a plane containing the lever pivot axis; a pair of electrical conducting members secured to said base and extending into said opening at spaced locations, said pivot bar translationally movable between a position making contact with said conducting members and a position breaking contact with said conducting members; a spring mounted in said base opening operatively engaging said pivot bar to urge same translationally toward one of said pivot bar positions, said lever urging said pivot bar translationally to the other of said pivot bar positions in opposition to said spring upon rotation of the lever away from said idling position; and a stop member formed on said base on a side of said translational displacement plane opposite the side at which said cable is secured to the lever, said stop member engaging a first surface of said lever as the lever nears said idling position whereby the bias of said control cable thereupon urges said lever to rotate about the point of engagement of the lever and stop member toward said idling position, and simultaneously urges said pivot bar translationally to said other of said pivot bar positions in opposition to said spring so as to normally maintain said pivot bar at said other position when the lever is at said idling position.
 8. The switch of claim 7, wherein said stop member is engageable with a second surface of said lever to limit rotation of the lever in a direction away from said idling position. 